What is the maximum number of unique addresses available in an IPv4 setting?

The maximum number of unique addresses available in an IPv4 setting is determined by the structure of the IPv4 address, which consists of 32 bits. Each bit can be either a 0 or a 1, allowing for a total of 2 options for each bit. Therefore, to calculate the total number of unique addresses, you raise 2 to the power of the number of bits:

2^32 = 4,294,967,296 unique addresses.

This vast number of addresses was originally intended to accommodate the rapidly growing number of devices connected to networks globally. However, due to the increasing demand for IP addresses, the allocation of these addresses has become a critical concern, eventually leading to the development of IPv6 which offers an even larger address space.

The other choices reflect calculations based on different numbers of bits and do not correspond to the 32 bits used in IPv4 addressing. For example, 2^8 and 2^16 pertain to 8-bit and 16-bit address spaces, respectively, which would allow far fewer unique addresses than what is necessary for global networking. Meanwhile, 2^64 would typically refer to theoretical address spaces used in other contexts such as IPv6 or specific types of data structures